1. Technical Field
The present invention relates to a gate valve used for a vacuum processing apparatus, and more particularly to a gate valve used for a substrate processing apparatus for processing a semiconductor substrate and a substrate processing system having the same.
2. Background Art
Generally, a semiconductor substrate is manufactured through several steps of vacuum processing processes. Various types of vacuum processing processes such as a deposition, an etching, and an ashing are performed in a process chamber having a vacuum state lower than a predetermined air pressure. A yield is one of very important elements in a semiconductor manufacturing process. In order to increase a yield in a semiconductor manufacturing process, a substrate processing system with various structures is used. For example, the substrate processing system includes an in-line type substrate processing system in which a plurality of process chambers are successively arranged and a cluster type substrate processing system in which a plurality of process chambers are radially arranged.
FIG. 1 is a view illustrating an example of a convention cluster type substrate processing system.
Referring to FIG. 1, a cluster type substrate processing system 70 includes a first transfer chamber 75 having a polygonal cross section structure. A plurality of process chambers 76, 77, 78, 79, and 80 and one loadlock chamber 74 are radially arranged to be coupled with the first transfer chamber 75. Each of gate valves 92, 93, 94, 95, and 96 is disposed between the first transfer chamber 75 and each of the plurality of process chambers 76, 77, 78, 79, and 80. Similarly, a gate valve 91 is disposed between the first transfer chamber 75 and the loadlock chamber 74. A second transfer chamber 73 is coupled with another surface of the loadlock chamber 74 and the gate valve 90 is disposed between the loadlock chamber 74 and the second transfer chamber 73. An EFEM (Equipment Front End Module) 71 equipped with a plurality of cassettes 72 is disposed in front of the second transfer chamber 73.
A transfer robot (not shown) operating in a vacuum state is installed in the first transfer chamber 75, and a transfer robot (not shown) operating in an atmospheric pressure state is installed in the second transfer chamber 73. The loadlock chamber 74 maintains an atmospheric pressure state while performing a substrate exchanging operation with the second transfer chamber 73, and maintains a vacuum state while performing a substrate exchanging operation with first transfer chamber 75. The first transfer chamber 75 maintains a vacuum state and performs a substrate exchanging operation with the plurality of chambers 74, 76, 77, 78, 79, and 80 connected to circumferences of the first transfer chamber 75.
Such a cluster type substrate processing system 70 has a structure, which can increase a yield by simultaneously processing a plurality of substrates to be processed through the plurality of process chambers 76, 77, 78, 79, and 80 radially arranged in the circumferences of the first transfer chamber 75. However, when one of the plurality of process chambers 76, 77, 78, 79, and 80 is broken, there is a disadvantage in that a broken chamber should be replaced or the substrate processing system 70 should be totally stopped in order to repair the broken chamber.
Meanwhile, in general, a substrate entrance provided between chambers is locked through the gate valve as described above. The gate valve uses a sealing member such as an O-ring. The sealing member corresponds to a consumable member and is replaced after using the sealing member during a certain period. However, when it is required to replace the sealing member, an operation of the substrate processing system should be stopped, so that it also causes a yield reduction. In a case of the in-line type substrate processing system, there exists the same problem as described above as well.
As described above, in a case where two chambers are coupled with each other through the gate valve, when it is necessary to stop an overall operation of the substrate processing system for maintenance of one of the chambers or to stop an overall operation of the substrate processing system for maintenance of the gate valve, a main problem causing a yield reduction occurs.